Rotary mercury interrupter



May 7, 1929. P. H. PlERcE Er A1.

ROTARY MERCURYv INTERRUPTER Filed Oct. 20, 1926 Patented May 7, 19.129.

UNITED! STAT-Esy y 1,711,689 PATENT OFFICE.-

PAULH. PIERCE, 'or WEsrrIELD, NEW JEESEY, AND WINTHEOP .1'. MEANS, oE'BEooK- LYN, NEW YORK, AssIeNoEs To BELL. TELErHoNE LAEoEAToEIEs, INCORPO- EA'rED, 0E NEW Yoan, N. Y., A CORPORATION or NEW YORK. l

-EOTAEY MERCURY rN'rEmatrr'rEE.v

v Application `filed October 20, 1926, Serial No. 142,811..

This invention relates to rotary interrupts.

ers and more particularly to lmercury interrupters. I Interrupters consisting of two insulated v chambers containingfmercury and arranged to-be simultaneously rotated so as to permit the'mercury .to periodically contact through openings in the'insulating partition have been used in the past. The interrupter of this invention is an improvement-in this vgeneral type' and in a preferred embodiment consists of two metal discs each having an annular groove formed on theinner face, so that when the discs are'clamped together with an insulating partition separatingthem, these grooves form a pair of annular chambers in which a definite quantity of mercury placed. When the discsv are mounted o nl a horizontal shaft and rotated, openings in the insulating partition permit the mercury in the two chambers to come together thus making'contact between the two rings, the length of the make and break periods being controlled by the quantity of mercury, the shape and spacing of the openings in the partition,

and the speed of rotation. Y

The use of annular chambers gives in effect columns of mercury whose free surface is small, thus minimizing the tendency for 3o turbulence and giving accurate control ofthe make and break intervals. The shape of the chambers also permits the switch to operate satisfactorily even whenthe shaft is inclined at a considerable angle. The form of the interrupter makes it very easy to construct and permits the assembly to be hermetically sealed.

This invention can be more readily runderstood by 'reference to the foll wing detailed 4o description in connection wit the'drawing in which: 'l 4 Figs. 1 and 2`show respectively, a front elevationpartly in section anda sectional side elevation of one embodiment of the Yinventon. g

Referring to the drawing, there are' shown two metallic discs 4 and 5 provided with annular grooves 6 and 7, respectively. These discs are clamped together with an insulating partition 8 of asbestos board between them,

and provided with an insulating hub 9 arranged to be mounted on a horizontal shaft 10. The screws 16 for clamping the assembly are set in insulating bushingsv so that the discs are insulated from each other. The 55 grooves 6 and 7 and separating partition 8 form two insulated chambers in which` is placed a definite quantity of mercury y11. 'I he partition 8 is provided with two o penings 12 and 13 which, when the discs are rotated, 60 permit the mercury inthe two chambers to come in contact ma i'ng a connection between the two discs. Brushes 14 and h15 are in contact with the discs and areprovided for connecting the interrupters in a suitablecircuit. The inner rims of the discs are provided with fillets and the diameter of the partition is made slightlysmaller than that of the discs "to permit theuse of sealing compound for hermetically sealing the discs. A tube 17 is provided .through the wall of fthe/disc 5 so that the air may be -pumped out and the space above the mercury filled with an inert gas after vwhich operation, the tube issealed. 1 .Y- g p' y The length of the make and break periods is determined by the speed of rotation, the n number, shape and size ofthe openings in the l partition and the quantity of mercury, any or all of which may be varied to give the 80V desired interruption characteristic.

The hape of. the .switches makes them readily a apted to be mounted on a common shaft 1n m ltiple units such as are often rel' quired in a elephone plant. If desired, for example for obtaining a required interruption characteristic, .two or more discs may bemeunted together to form independent or cooperating chambers. y

What is claimed'is: 1

1. 'An electric switch comprising two annular chambers, an insulatingv artition therebetweenhaving an opening t erein, a liquid conductor partially filling each of the two chambers, and means for simultaneouslyV rotating said chambers.-

2. An electric switch comprising a pair of rotatable discs of conducting material, an

" annular '(groove in one face of each of'said discs, sai grooves havin substantially equalA diameters, a partition o insulatin material having an opening therein, means or clamping said discs together. to form twoannular chambers havingv an insulating wall therebetween formedby said partition and communicating with each other by means of said openin and ali uid conductor partially filling eac of the c ambers.

3. An electric switch comprising a pair of -rotatable rings. of conducting material, van

annular groove in one face .of said rings, said grooves having substan tiallyv equal diameters, a hub of insulating material on 'of the chambers, and means for. hermetically sealing .the chambers.

4..An electric switch comprising a 'pair of rotatable rings of. conducting material,

eachl having a substantially equal diameter annular groove in one facei of` relatively small cross-sectional area, s ald rings being rigidly fastened together with an' insulating partition therebetween to form two annular chambers a liquid conductor partially filling the two chambers, and openings in said par- 'liquid tition through'which the liquid in Ysaid chambers' periodically makes contact when theopenino in said insulating member, and

means o r rotating said member to bring said opening between said columns whereby the orming said columns is permitted to come in contact. 6, An electricswitchcomprising two adjacent and relatively slender curved columns of mercury of the vsame' radius of curvature and .cross-section and-having a common axis, an insulatingpartition separating said columns, an opening in saidpar'titiomand means for rotating said partition'v to periodically bring4 said .opening between -said columns.

In witness whereof, we hereunto subscribe our names 'this 19th day of October, A, D.,

192.6. PAUL. H. PIERCE. wIN'rHROP J. MEANS. 

